Concrete form tie assembly

ABSTRACT

A concrete form wall is braced inwardly (i.e., on the concrete pour side) by a form tie assembly comprising at least two rod members mechanically spliced together. The tie rods are provided at least with serrated end sections that are overlapped and interconnected by a collar member that is drive fitted onto the cooperating overlapped serrated end sections to bind the tie rods together against tensile load forces resulting from the weight of the concrete pour bearing against the form wall.

Uni td States a ten" [72] Inventor Ottls 1D. Pruitt 671,829 4/1901 Lewis 287/104 X Mlossyroclt, Wash. 1,078,007 1 H1913 Stange 249/213 X [21] App]. No. 656,762 1,935,218 11/1933 Umbach 249/190 [22] Filed July 28, 1967 2,100,614 11/1937 Schenlc... 25/131 T UX Patented 1971 2,164,592 7/1939 Pilj 249/213 X 1 Assignees Arthur n n; 2,475,890 7 1949 Hamilton... 25/131 'r ux William '11. Neelamls 2,823,441 2/1958 Wil1iams..... 249/190 M syr r Washpart interest to each 2,962,789 12/1960 Williams. 249/190 X 1,603,748 10/1926 Davis 24 /49 [54] CQNCRETE FQRM THE ASSEMBLY Primary Examiner-J. Spencer Overholser 5 maims, 6 Drawing Figs. Assistant Examiner-Michael 0. Sutton 52 111.s.c1 249m, mummy Seed Berry & Dowwy 249/40, 249/213, 287/104 [51] 1111. C1 ..1E04g 1111/20, ABS'llmAlC'll: A concrete form wall is braced inwardly (i.e., E 4g 17/ on the concrete pour side) by a form tie assembly comprising [50] Field of Search 249/40, at least two rod members mechanically spliced together. The 190, 213, 25/131 T tie rods are provided at least with serrated end sections that are overlapped and interconnected by a collar member that is [56] defences Cited drive fitted onto the cooperating overlapped serrated end sec- UNITED STATES PATENTS tions to bind the tie rods together against tensile load forces 53,219 3/1866 Fawcett 287/104 resulting from the weight of the concrete P bearing against the form wall.

PAIENIED nEc I 449?! SHEE'I 1 BF 2 INVENTOR. OTTIS D. PRUHTT AT TOWN E VS CONCRETE FORM TIE ASSEMBLY This invention relates to apparatus for tying and spacing concrete forms. More particularly this invention relates to form tie structures of the type employed for interiorily bracing concrete fonns.

Interior bracing of concrete forms, that is to say with tiedown structures (commonly called "concrete form ties")' that are permanently imbedded in freshly poured concrete contained by the thusly braced fon'ns, is a commonly employed technique where large expanses of vertical forms or where multiple pours--one on top of the other-are required. Typical applications include concrete fonns for dam faces, large buildings, large retaining walls, and other relatively thick concrete structures.

Concrete forms ties" presently in use for bracing the upper sections of a concrete form comprise a pigtail anchor tie rod that is embedded in the top of the previous pour or in bed rock, etc., in the case of the first pour, an elongated coupling tie rod that is welded to the pigtail anchor tie rod end, extending upwardly toward the form, a shebolt that extends through the form and threads onto the coupling tie rod, a cathead" bracket on the exterior of the form through which the shebolt extends, and a locknut threaded onto the outer end of the shebolt and against the bracket. When the pour has been made and is set up, the locknut is loosened from the bracket and the shebolt unscrewed from the coupling tie rod and pulled out of the face of the pour for reuse, the pigtail tie rod anchor and coupling tie rod remaining within the pour. This type of "concrete fonn tie" requires a considerable amount of on-the-job fabrication in cutting the tie rod members to proper length and in welding the coupling tie rod to the pigtail tie rod anchor. Furthermore, the welded joint thus formed between the two tie rod sections has an unknown strength which is only proven inadequate by collapse of the form during a pour. Because the strength of the joint is unknown, a large excess of these concrete form ties is employed to ensure the existence of an adequate safety factor-thereby increasing the time and expense of on-the-job fabrication.

A primary object of this invention is to provide an improved "concrete form tie" that employs nonwelded joints of sufficiently predictable strength as to enable a reduction in on-thejob fabrication time and expense with no sacrifice of an adequate safety factor.

This and other objects and advantages of the present invention will become apparent from the following disclosure and the accompanying drawings of which:

FIG. ll illustrates in elevation a typical application of one embodiment of the concrete form tie of this invention;

FIG. 2 illustrates an unassembled joint in accordance with this invention;

FIG. 3 illustrates an assembled joint in accordance with this invention;

FIG. 4 illustrates a sleeve employed in a joint in accordance with this invention;

FIG. 5 illustrates in elevation another application of one embodiment of the concrete form tie of this invention; and

FIG. 6 illustrates still another application of one embodiment of the concrete form tie of this invention.

In brief, the concrete form tie of this invention comprises at least two tie rod members provided with cooperating interlocking serrated or toothed faces that are bound together in a mechanical splice by a drive-fitted collar or sleeve. These members may be formed of cold-rolled steel or other suitable rod stock and the collar or sleeve formed of thin-wall seamless steel tubing or other suitable stock.

At least one of the tie rod members will be a coupling tie rod anchored at one end to a shebolt form connection and anchored at the other end to another tie rod of the pigtail anchor type or of the coupling tie rod type, depending upon the application. The cooperating serrated or toothed sections may be rolled, stamped or otherwise formed on the tie rod members and may be sawtoothed, notched or other suitable configuration.

The collar or sleeve preferably has a beveled leading edge to facilitate drive-fitted engagement of the collar. The longitudinal length of the collar is such as to ensure adequate engagement of a sufficient number of the cooperating serrations to develop the required splice strength. The cross section of the collar also is such that the tubular collar is deformed as it is driven into a coupling position so as to tightly clamp the cooperating serrated surfaces together.

Referring to FIGS. 2-4, the mechanical joint embodied in this invention is formed by slipping a tubular collar or sleeve 10 onto the serrated end 12 of the tie rod member 14 with its tapered leading edge 11 opening toward the serrated end of the tie rod member 14, overlaying the serrated end 16 of another tie rod member 18 is a desired amount on the first tie rod member M, and driving the collar onto the overlayed serrated sections 12 and I6 to form the mechanical splice. In the usual installation, the collar will be driven over the second tie rod member 18 until the trailing edge of the collar is flush with the end of the second tie rod member.

lFlG. 1 shows the invention applied to a typical vertical form installation for a second pour wherein the lower edge of the form 21 is held against the upper edge of a first pour 22 by a horizontal pigtail anchor assembly 20. A shebolt and cathead assembly 30 is applied to the upper edge of the form and angled downward and inward as shown. A coupling tie rod member 32 with a serrated lower end section and a threaded upper end section is screwed into the shebolt and spliced to the exposed upper serrated end of a pigtail anchor 34 by a drive-fitted collar 36, the pigtail anchor having been embedded in the surface of the previous pour for that purpose. An upper horizontal pigtail assembly 38 is provided in the upper end of the form to serve the purpose of the assembly 20 when the third pour is made. The lengths of the cooperating serrated surfaces on the tie rod members are sufficient to permit the necessary overlap to couple the pigtail anchor 34 to the shebolt and cathead assembly 30.

FIG. 5 illustrates an embodiment wherein the entire lengths of the tie rod members are serrated such as would be the case if they were cut to the lengths desired from a longer length of rod stock supplied as a shelf item". In this case, a short angled tie rod member 40 is threaded at one end and serrated at the other end so that it may be screwed into a shebolt and cathead assembly 42 and spliced to an intermediate coupling tie rod member 44 by a drive-fitted collar 46. The anchor tie rod member 48 in this case is not of the pigtail type, the serrations being sufficient to confine it in the previous pour, and is spliced to the lower end of the intermediate member 44 by a drive-fitted collar 50. The serrations may be notched as shown or of a sawtooth configuration. This embodiment further illustrates the use of this combination to anchor the lower edge of the form 52 to the upper portion of the previous pour.

IF IG. 6 illustrates an embodiment wherein two parallel forms 54 and 56, as for a thick concrete wall, are interiorily braced by two coupling tie rod members 60 and 62 that are spliced together by a drive-fitted collar 64 clamping the respective cooperating serrated end sections together and that are threaded into respective shebolt and cathead assemblies 66 and 68 on the forms.

It is to be understood that a plurality of tie rod assemblies usually would be provided for adequate support of each form wall, some extending from the upper section of the form, some from intermediate sections of the form, and so forth, and that these may be assembled at a variety of angles and anchored in various ways, all depending upon the requirements of the particular installation. It is also to be understood that no other element or member is required or employed for each splice other than the overlapped cooperating serrated tie rod sections and the drive-fitted collar that firmly binds the two serrated sections together.

It is believed that the invention will have been clearly understood from the foregoing detailed description of my nowpreferred illustrated embodiment. Changes in the details of construction may be resorted to without departing from the spirit of the invention and it is accordingly my intention that no limitations be implied and that the hereto annexed claims be given the broadest interpretation to which the employed language fairly admits.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In combination, a fonn wall, a concrete fonn tie assembly for bracing said form wall comprising two tie rod members, each member having a serrated section which includes a toothed, substantially fiat face disposed in a plane generally parallel to the longitudinal axis of said section for allowing adjustment movement of said sections relative to one another, at least one of said sections being of substantial length for longitudinal adjustment relative to the other section, and a collar drive fitted over said engaged serrated sections so as to finnly splice the serrated sections together in any adjusted position, securing means for securing one of said members to said form wall, and supporting means for supporting the other of said members whereby said form wall is supported against the weight of a concrete pour by tensile forces imposed in said form tie assembly, one of said tie rod members being an intermediate coupling tie rod member provided withadditional serrations along its entire length and wherein said securing means includes a short angled tie rod member having a substantially flat toothed face and a second collar drive fitted over said intermediate coupling tie rod member and said short angled tie rod member.

2. The combination of claim 1 wherein said supporting means includes a previous pour in which said member is implanted and said securing means includes a shebolt and cathead assembly.

3. The combination of claim 1 wherein said securing means includes a shebolt and cathead assembly and wherein one of said tie rod members is relatively short and is provided with a threaded end section for screw attachment to said shebolt and cathead assembly.

4. The combination of claim I wherein said supporting means includes an oppositely positioned form wall.

5. The combination of claim 1 wherein said collar is provided with a bevelled leading edge.

l 1 I! i i 

1. In combination, a form wall, a concrete form tie assembly for bracing said form wall comprising two tie rod members, each member having a serrated section which includes a toothed, substantially flat face disposed in a plane generally parallel to the longitudinal axis of said section for allowing adjustment movement of said sections relative to one another, at least one of said sections being of substantial length for longitudinal adjustment relative to the other section, and a collar drive fitted over said engaged serrated sections so as to firmly splice the serrated sections together in any adjusted position, securing means for securing one of said members to said form wall, and supporting means for supporting the other of said members whereby said form wall is supported against the weight of a concrete pour by tensile forces imposed in said form tie assembly, one of said tie rod members being an intermediate coupling tie rod member provided with additional serrations along its entire length and wherein said securing means includes a short angled tie rod member having a substantially flat toothed face and a second collar drive fitted over said intermediate coupling tie rod member and said short angled tie rod member.
 2. The combination of claim 1 wherein said supporting means includes a previous pour in which said member is implanted and said securing means includes a shebolt and cathead assembly.
 3. The combination of claim 1 wherein said securing means includes a shebolt and cathead assembly and wherein one of said tie rod members is relatively short and is provided with a threaded end section for screw attachment to said shebolt and cathead assembly.
 4. The combination of claim 1 wherein said supporting means includes an oppositely positioned form wall.
 5. The combination of claim 1 wherein said collar is provided with a bevelled leading edge. 